Save Endangered Right Whales

A species is undoubtedly in trouble when each member is identified by a serial number and listed in a catalogue along with an accompanying mug shot. The species in question is the North Atlantic right whale, which number only about 350.

Boat collisions and injuries from fishing lines have contributed greatly to the death of right whales. But scientists are optimistic that better knowledge of the creature's biology and behaviour coupled with recent technological innovations could enable them to rescue the species.

Researchers developed a new type of buoy that will alert ships to the presence of whales nearby. Fishermen, meanwhile, are working to design
fishing lines that hug the ocean floor, which would prevent entanglements with whales. Researchers at Cornell University have designed an underwater microphone to record whale "talk." The device, containing a computer and hard disks that can store up to two months of recordings, lies on the ocean floor and eventually pops up to the surface so scientists can collect the data.

The recordings and the information about the whales' wanderings is giving scientists an extraordinary picture of whale life. They show whales coming together in big, very socially active groups, where they scream away for a few hours then go away and start up some place else.

In another strand of the research, marine biologists have obtained skin samples of right whales and are examining them to determine the health, gender ratio, and genetic makeup of the population. Scientists have skin samples from about 75 per cent of the species. Each whale has a unique set of white patches on its skin – callosity patterns – which serve as natural identification tags for each animal.

Scientists also photograph the backs of these animals, which are decorated with scars, most often from collisions with ships and struggles with fishing lines – almost two-thirds of the population have scarring. Almost the entire population of 350 right whales has been photographed. Together, the techniques have given scientists the best profile of any endangered species yet. They have combined at least 20 years of right whale observations with genetic profiles of at least 75 per cent of the species to create one of the most detailed profiles of an entire species.

From DNA samples of 200 of the whales, the researchers found that all of those sampled were descended from only five females. Because the population is small and lacks genetic diversity, scientists are concerned that the species may be more vulnerable to threatening diseases.

The good news is that there is roughly an equal number of males and females. The bad news, however, is that females produce a calf only every three years, or even longer. Still, there is some more news. In 2001 scientists had "a bumper crop of calves" – they saw 30 in all. But this is not a recovery, scientists say, explaining that the whales' birth rate is unpredictable. In 2000, only one calf was born. So the 2001 birth rate need to continue for about ten years to feel like the population has some sort of buffer zone.

An international consortium of researchers is committed to developing whale-watching technology and modifying fishing equipment that will reduce the number of injuries and deaths. Scientists will know if they are successful if they see a reduction in the number of scars.

Bijal P. Trivedi. National Geographic Today. 2001

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